A Novel Fiber Optic Delamination Detection Scheme: Theoretical and Experimental Feasibility Studies

Delamination detection is important in ensuring the safety and timely repair of structures. In this paper, a novel technique for detecting delamination is proposed. By embedding an optical fiber inside a structural component, the integrated strain along the fiber can be determined. With a load moving along the component, a plot of integrated strain vs load position can be obtained. By correlating changes in the plot with the presence of delaminations, a simple loading test can be employed for delamination detection. The objective of the present investigation is to assess the feasibility of the proposed technique. Experimentally, to ensure the measurement of small length changes as a result of delamination, a highly sensitive interferometer is developed. Laboratory tests are carried out on simply supported beams and beams on elastic foundation. To compare with experimental measurements, finite element analysis is carried out to obtain numerical results. The experimental and numerical results correlate reasonably well with one another. The findings of this investigation demonstrate the potential of the technique and warrant further developments for practical applications.